The Inflammatory Mediator/Bronchoscopy Core plays a central role in research in the Cystic Fibrosis Research Core Center by providing the ability to sample directly the inflamed airway in CF patients and control subjects and to study the cells and inflammatory mediators found at that site. It disseminates samples to researchers for whom they might otherwise be unavailable and provides access to sensitive standardized assays of cytokines and lipid-derived inflammatory mediators to Center investigators. This Inflammatory Mediator/Bronchoscopy Core performs the following functions: a) it obtains and processes bronchoalveolar lavage (BAL) samples and bronchial epithelial cells obtained by bronchoscopy brushing from CF patients and normal volunteers; b) it provides appropriately handled epithelial and inflammatory cells and fluid samples from these bronchoscopies and lavages to Center investigators for investigators of immune and inflammatory processes in CF, and coordinates the efforts of Center investigators to optimize the use of these invaluable specimens; and, c) it performs routine assays of cytokines, other inflammatory mediators, proteases and protease inhibitors on bronchoscopy samples and on other samples provided by Center investigators. The Core provides sensitive, reliable, cost effective assays, maintaining high quality control and standardization. By having these functions provided by this Core, the utilization of invaluable patient material is optimized, interaction among investigators is stimulated, and the highest standards of clinical and analytic procedures are maintained while keeping costs at a minimum.